How to play International draughts

The 10×10 game with twenty men each: backward captures, the largest capture rule, flying kings, numbered squares and the FMJD draw counts, shown on the board.

International draughts gives each side twenty men on a 10×10 board, and asks you to count. Men capture forwards and backwards, kings fly along open diagonals, and when several captures are possible you must take the largest. Its capture and crowning rules match Brazilian draughts, but this page has everything you need to play. The diagrams are example positions, with White at the bottom.

Fifty squares and twenty men

The 50 dark squares are numbered from the top row as White sees it, five to a row. Black starts on squares 1 to 20 and White on squares 31 to 50, with ten empty squares between them. White moves first, towards the low numbers.

The starting position, White to move. Only the men on squares 31 to 35 can move, which gives nine first moves, from 31-26 to 35-30.

Men step forward and capture both ways

A man steps one square diagonally forward onto an empty square. Its capture can go forwards or backwards: it jumps a neighbouring enemy piece and lands on the empty square just beyond.

White to move: the black man on 33 is behind the white man on 28, capture is compulsory, and 28x39 is the only legal move.

You must take the largest capture

A capture must be finished, so while the piece can jump again it goes on. Among all the captures on offer, you must choose one that takes the most pieces. A king counts as one piece, the same as a man. If several routes take the same number, you choose freely. With twenty men each there can be many routes, so make a habit of following each capture to its end before you pick up a piece.

White to move: 33x11 is the only legal move. It takes the man on 28 and the king on 17, two pieces, and the other capture, over 29, would take one.

Flying kings

A man that ends its move on the far row is crowned: White on squares 1 to 5, Black on squares 46 to 50. A king moves any distance along an open diagonal, in any direction.

The king on 28 has 17 moves: nine along the long diagonal from 46 to 5, and eight along the diagonal from 6 to 50.

To capture, a king crosses one enemy piece with a free square behind it, from any distance, and may land on any free square beyond. If one of those squares lets the capture go on, it must stop on a square that does. Jumped pieces stay on the board until the move is over, so none can be jumped twice and each one still blocks the way.

The king on 46 takes 32, 29 and 39, stopping on 23 and on 34 to keep going, so the only moves are 46x43 and 46x48. From 43 the man on 27 looks open, but 32 stays on the board until the move ends and blocks the way, so 27 survives.

Passing over the far row

The far row crowns only a man that finishes its move there. One that lands on it in the middle of a capture and has to go on is still a man when the move ends.

White's only move is 11x13. The man touches square 2 on the far row, but it must go on over 8, so it finishes on 13 as a man.

Making the other side capture

Your opponent must capture too, and must take the largest capture on offer, so you can sometimes decide where their pieces end up.

White is a piece down and plays 38-33. Black's only legal reply is 11x30, which takes two men and pulls the king to 30, beside the man on 35. Then 35x4 takes the king and the men on 20 and 10, and stops on the far row to crown, leaving five pieces each and the only king with White.

Forcing captures shows how to look for these.

How a game ends

A side that has no pieces left on its turn loses, and so does a side whose pieces are all blocked. A draw can be proposed with Offer a draw. The other draws come from Annex 1 of the FMJD rules, and this site applies them by itself.

Repetition. The same pieces on the same squares, with the same side to move, for the third time.
Twenty-five moves. During 25 successive moves for each player only kings have moved, with no man moved and no capture.
Sixteen moves. Three kings, two kings and a man, or a king and two men against one king: both players may play at most another 16 moves. A capture during those moves does not restart the count.
Five moves on the long diagonal. Once the lone king is the only piece on the long diagonal, from square 46 to square 5, at most five more moves each. The wording of that rule is unclear, and this is how this site reads it.
Five moves in the smallest endings. Two kings, a king and a man, or a king against one king: at most five more moves each. If a capture brings a sixteen-move ending down to this one, the earlier deadline applies.

A win reached on the last counted move beats the draw.

Three white kings against a lone black king on 28, the only piece on the long diagonal. From here the game can last at most five more moves each, even if the king then leaves the diagonal.

Moves in numbers

Moves are written in square numbers. A quiet move, one that captures nothing, joins start and end with a dash, as in 33-28, and a capture uses an x, as in 28x39. A multiple capture writes only its start and end, so 46x43 does not mention 23 or 34. Landing squares are added only when two legal captures share a start and an end but take different pieces. For the other rule sets, see the notation page.

To practise, work through the International lessons, then start a game on the big board.